{"id":11587,"date":"2026-09-04T18:53:43","date_gmt":"2026-09-04T10:53:43","guid":{"rendered":"https:\/\/www.54iter.cn\/?vuln=cve-2026-55546"},"modified":"2026-09-04T18:53:43","modified_gmt":"2026-09-04T10:53:43","slug":"cve-2026-55546","status":"publish","type":"vuln","link":"https:\/\/www.54iter.cn\/?vuln=cve-2026-55546","title":{"rendered":"CVE-2026-55546 [CRITICAL] &#8211; QWED-MCP is a deterministic verification gateway for MCP. Prior to 0.2.1, verify_math_expr"},"content":{"rendered":"<p>QWED-MCP is a deterministic verification gateway for MCP. Prior to 0.2.1, verify_math_expression() in src\/qwed_mcp\/engines\/math_engine.py passes attacker-controlled expression and claimed_result strings directly to SymPy&#8217;s parse_expr() after only normalizing caret syntax to Python exponent syntax, without restricting global_dict, removing Python built-ins, or validating the expression AST. Because parse_expr() calls Python&#8217;s eval() with built-ins available, an attacker who can cause a downstream caller to pass untrusted input to this public library function can use Python import functionality to execute arbitrary operating-system commands as the qwed-mcp process user, read or modify accessible data, exfiltrate process secrets, or reach internal services. The default MCP tool registry does not expose verify_math_expression(), so exploitation requires a downstream integration that invokes the library API with attacker-controlled input. This issue is fixed in version 0.2.1.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>QWED-MCP is a deterministic verification gateway for MCP. Prior to 0.2.1, verify_math_expression() in src\/qwed_mcp\/engines\/math_engine.py passes attacker-controlled expression and claimed_result strin<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-11587","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/11587","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln"}],"about":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/types\/vuln"}],"wp:attachment":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=11587"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=11587"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=11587"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}